Incandescent lamp.



F. DICKENSCHIED. INCANDESCENT LAMP. APPLICATION man JUN 26. 1912.

Witnesses.- fizvemfiar': {W6 5 W. fi'ztz .Uzckezwcfizsd, H's At tarnsy Patented Aug. 10, 1915.

ED STATES'PATENT OFFICE. j

FRITZ mcxE scErEn, or BERLIN, GERMANY, ASSIGNOB 'ro GENERAL Enncrnic comm, A. CORPORATION 01? mm YORK.

INCANDESCENT- LAMP.

Specification of Letters Patent.

Application filed July 26, 1912. Serial No. 711,612.

To all whom it may concern:

Be it known that I, Fnrrz DIonENsomnD, asubject of the Emperor of Germany, residing at Berlin, Germany, have invented certain new and useful Improvements in In- I candescentLamps, of which the following increase its radiation.

is specification.

The present invention relates to incandescent lamps, and comprises an improvement in the, mounting of'metallic filaments therein. 1

My invention is directed to the prevention of deleterious effects at regions of contact of the filament and its supports. In accordance with my invention the temperature of this region of the filament is lowered lower melting point than the filament.

cause of the high operating temperature of the filament, the supports are highly heated at the region of contact. This results in some cases in gases being given oil which after a time result in a lowered vacuum in v the lamps and a consequent deterioration of the filament by electric discharges. In some cases it may even happen that the holder wire is melted at its point of cohtact with the filament, thereby releasing the filament. Even whenit is attempted to prevent the overheating of the supporting wire by increasing its diameter, alloys are apt to be formed at its contact with the filament r eediting in the filaments burning through at this point. As it is desirable to make the supports somewhat springy to fprevent displacement on the part of the lament, the

size of the supporting wires is limited as the lar er wires are not sufiiciently resilient;

As a ove indicated, the excessive heating of the holders by contact with the filament is prevented in accordance with the present invention by increasing the surface of the filament at the contact region and thereby increasin the radiation. As the, energy is thus' dissipated more readily, thetemperature is necessarily lowered. In the case of round filaments my invention may be readily carried out by locally flattening the filament as by pressing or rolling. This local flattening may be produced by simply pressing the filament 2 by hand with pinchers at the region 2, where it comes into contact with holder wires 3. In some cases the local flattening of the filament may advantageously take place after the filament has been wound upon the supports, and in other cases the filament is pressed flat at regions at measured distances corresponding with the regions of contact with the holders.

Of course, it will be understood that m invention is not limited to a filament mount containing a plurality of loops as illustrated in Fig. l but is equally applicable to a mounting in' which a simple looped. filament is provided with a. sin le support intermediate to its ends to hol it in position.

What I claim as new and desire to secure by Letters Patent of the United States, is,-

1. In an incandescent lamp, the combination of a support, an elongated, slender metallic filament. held thereby, the radiating surface of said filament being greater at the region'of contact with the support than elsewhere, whereby the radiation is increased at this region.

2. In an incandescent lamp, the combination of a holder, a metallic filament supported thcreb at an intermediate point, said filar'nent eing locally flattened at the region of contact with the holder.

In witness whereof, I have hereunto set my hand this 12th day of July. 1912.

FRITZ DICKENSCHIED.

Witnesses:

\VoLnEMAn Haur'r, fllnwnr ll asrnn.

Patented Aug. 10, 1915.- 

